Set Image and Registry Seperately in Otel Collector

[afscrome]

Rather than fudge the registry into the image name, set the registry property explicitly.

For some context of why this matters to me - my org's build agents have locked down firewalls, and we have to rewrite public registries to internal mirrors - we do this by looking at the Registry property in a BeforeStart hook - see more at https://youtu.be/u0iK6Bv5BZ0?si=AtJ_DmYCn1t0Mq5f&t=1124 .

PR Checklist

• Created a feature/dev branch in your fork (vs. submitting directly from a commit on main)
• Based off latest main branch of toolkit
• PR doesn't include merge commits (always rebase on top of our main, if needed)
• Code follows all style conventions

Other information

[Copilot]

Pull request overview

This PR refactors the OpenTelemetry Collector integration to separate the registry and image properties when configuring the container, enabling registry rewriting in BeforeStart hooks for organizations with locked-down firewalls that need to redirect to internal mirrors.

Key Changes

• Changed from passing the full image path (including registry) via WithImage to separating the registry and image using WithImage and WithImageRegistry respectively
• Now uses settings.Image and settings.Registry separately instead of the computed settings.CollectorImage property

[afscrome]

SurrealDb test failures seem unrelated to this change.

[aaronpowell]

SurrealDb test failures seem unrelated to this change.

re-ran and tests pass.

[afscrome]

@aaronpowell Can you reopen this. @martinjt Do you mind reviewing?